Australian public authorities responsible for construction have the opportunity to 'green' their procurement processes for improved environmental impact. One method of greening procurement is to use off-site manufacture (OSM). This method of production takes place distant from the construction site thus saving energy through waste reduction and reduced time for project completion. Scholars have listed the benefits of adopting OSM. However, an active program of OSM adoption has not been considered for the Australian construction sector. Proving a mechanism to assist with OSM adoption is the purpose of this research. The Australian state government procurement agencies are the potential key 'leading users' of OSM, but 'leading users' alone are unable to drive innovation adoption. They need to work with industry stakeholders for concept acceptance and implementation. This paper suggests that an OSM concept diffusion mechanism for the construction industry community of practice will result in increased used of OSM. The paper describes the development of an evolving OSM adoption decision-making tool. An action research approach was used because it is both a process for identifying a problem solution and implementing change. A quick-use decision-tree structure based on a question and answer model was the result of the development process. The decision tree leads to both options: traditional production on-site or modern production to off-site manufacture because green procurement is not always the available option, at present. This individual project OSM adoption decision-making tool can also be used for industry concept diffusion and changing industry practice through green procurement processes of 'leading users'.